interfere

UK: /ˌɪntə^rˈfɪə^r/ US: /ˌɪntɚˈfɪr/ ,(in′tər fēr′)

Inflections of 'interfere' (v): (⇒ conjugate)

interferes

v 3rd person singular

interfering

v pres p

interfered

v past

interfered

v past p

WordReference Random House Learner's Dictionary of American English © 2026

in•ter•fere /ˌɪntɚˈfɪr/   v. [no object* often;
~ + with + object] , -fered, -fer•ing. 

1. to hamper, hinder, or block someone or something:
   The television interferes with his studying.
2. to take part in the affairs of others;
   meddle:
   His in-laws were always interfering in his life.
3. Sport (in a game or sport) to get in the way of an opposing player illegally.
4. Physics to cause interference:
   My computer monitor interferes with the television reception.

See -fer-.

WordReference Random House Unabridged Dictionary of American English © 2026

in•ter•fere  (in′tər fēr′), v.i., -fered, -fer•ing. 

1. to come into opposition, as one thing with another, esp. with the effect of hampering action or procedure (often fol. by with):
   Constant distractions interfere with work.
2. to take part in the affairs of others;
   meddle (often fol. by with or in):
   to interfere in another's life.
3. (of things) to strike against each other, or one against another, so as to hamper or hinder action;
   come into physical collision.
4. to interpose or intervene for a particular purpose.
5. to strike one foot or leg against another in moving, as a horse.
6. Sport
   • to obstruct the action of an opposing player in a way barred by the rules.
   • [Football.] to run interference for a teammate carrying the ball.
7. Physics to cause interference.
8. to clash;
   come in collision;
   be in opposition:
   The claims of two nations may interfere.
9. Law to claim earlier invention when several patent requests for the same invention are being filed.
10. British Terms interfere with, [Chiefly Brit.] to molest sexually.

• Latin ferīre to strike; modeled on Middle French s'entreferir
• inter- + -fere 1520–30

in′ter•fer′er, n. 
in′ter•fer′ing•ly, adv. 
Synonyms

• 2. pry, intrude, encroach, interlope.
• 4. intercede.

Collins Concise English Dictionary © HarperCollins Publishers::

interfere / ˌɪntəˈfɪə/ verb (intransitive)

1. (often followed by in) to interpose, esp meddlesomely or unwarrantedly; intervene
2. (often followed by with) to come between or in opposition; hinder; obstruct
3. (followed by with) to assault sexually
4. to strike one against the other, as a horse's legs
5. to cause or produce interference

Etymology: 16th Century: from Old French s'entreferir to collide, from entre- inter- + ferir to strike, from Latin ferīre

ˌinterˈfering adjective